Glass fibers with fast wettability and method of producing same

A method of controlling the wettability of glass fibers in polyester matrices, wherein the glass fibers have a dried residue of an aqueous chemical treating composition having an aqueous emulsion of a thermoplastic film forming polymer having polar functionality, lubricant and coupling agent, comprising:

• a. formulating the aqueous chemical treating composition with nonaqueous components that have an amount of unsaturation of less than an average of 1.5 aliphatic double bonds per mole of each nonaqueous component and that result in a ratio of aliphatic unsaturation to aromatic unsaturation of not greater than around 0.1 as measured by IR absorptivity in film dried at room temperature where each component has less than an average of 1.5 aliphatic double bonds per mole for faster wetting of the glass fibers in the polymeric matrix and with higher values of the amount of unsaturation and of the ratio for progressively decreasing degrees of wettabillity, and to have less than one weight percent based on the aqueous composition of any chain extension inducing or condensation inducing reatants,
• b. treating glass fibers with the aqueous chemical treating composition,
• c. collecting the glass fibers as strands, drying the glass fiber strands at a temperature to discourage any crosslinking reactions.